Analyses of Fossil Bones of Nebraska. 



109 



cave, are also common in some seasons in the subterranean 

 rivers, and so also it is said the fish of the Green River are 

 to be found in times of flood in the rivers of the cave." 



In reply to a letter of inquiry from Professor Silliman 

 senior, Mr Agassiz made a few remarks on the presumable 

 primitive condition of the eyeless animals of the Mammoth 

 Cave. He says — " This is one of the most important ques- 

 tions to settle in natural history, and I have several years 

 ago proposed a plan for investigation, which if well consi- 

 dered, would lead to as important results as any series of in- 

 vestigations which can be conceived, for it might settle once 

 and for ever the question, in what condition and when the ani- 

 mals now living on the earth were first called into exis- 

 tence.''— {Silliman' 's American Journal, ix., No. 51.) 



Analyses of Fossil Bones of Nebraska. 



The results of the chemical examinations of the bones of 

 some of the fossil Mammalia from the tertiary formation of the 

 Mauvaises Terres of Nebraska, are interesting and remark- 

 able, as shewing the change which they have undergone dur- 

 ing the long period of interment. 



Part of Leg-Bone of Oreodon. 



Water of absorption, H = 2 - 70 



Organic Matter burned ) 



JL. . . + . \ = 2-50 



off by ignition, j 



Phosphoric Acid, P =36-77 



Carbonic Acid, = 3-00 



Fluorine, F = 3-20 



Lime, Ca=4893 



Silica, .. Bi= 340 



Trace of Fe and Mn, 



100-50 



Part of Scapula of Palseotherium. 



Combined with P, 



Ca „ „ C, 



Ca „ „ F, 



Ca „ „ sT(?).. 



Fe, 



Al, 



Mg, 



Mn, 



Na, 



Fe Si, insoluble, .... 

 Si dissolved by HC 1, 



2-50 



,. 3-20 



.32-00 



,. 4-20 



. 3-40 



z 34-00 



: 5-35 



r 3-66 



= 0-30 



4-50 



0-70 



0-90 



0-80 



2-04 



1-64 



0-30 



0-51 



10000 



